Evidence of genetic regulation of fetal longitudinal growth

Genetic as well as environmental factors are important determinants of fetal growth but there have been few studies of the influence of paternal factors on fetal growth.

To study the influence of paternal anthropometry on detailed measurements of offspring at birth.

A prospective cohort study involving biochemistry, and anthropometry, of mothers and fathers at 28 weeks gestation, and detailed anthropometry of children within 24 h of birth.

567 White Caucasian singleton, non-diabetic, full term pregnancies recruited from central Exeter, UK.

Paternal height, but not paternal BMI, was correlated with birth weight (r = 0.19) and with birth length (r = 0.33). This was independent of potential confounders and maternal height. All measurements of fetal skeletal growth including crown-rump, knee-heel and head circumference were associated with paternal height. Maternal height showed similar correlations with birth weight (r = 0.18) and birth length (r = 0.26). Maternal BMI was correlated with birth weight (r = 0.27) and birth length (r = 0.15). In a multifactorial analysis 38% of the variance in fetal height could be explained by gestation, sex, paternal height, maternal height, maternal glucose, maternal BMI, parity and maternal smoking.

Paternal height has an independent influence on size at birth. This predominantly influences length and skeletal growth of the baby. In contrast to maternal obesity the degree of paternal obesity does not influence birth weight. This work suggests that there is genetic regulation of skeletal growth while the maternal environment predominantly alters the adiposity of the fetus.